modularity as in kiwi-cron

Dockerfile

@@ -1,11 +1,14 @@
 FROM yavook/kiwi-cron:0.1
 LABEL maintainer="jmm@yavook.de"
 
+COPY requirements.txt /tmp/
+
 RUN set -ex; \
     \
     # create backup source
     mkdir -p /backup/source; \
     \
+    # duplicity software dependencies
     apk --no-cache add \
         ca-certificates \
         gettext \
@@ -20,11 +23,7 @@ RUN set -ex; \
         python3 \
         rsync \
     ; \
-    update-ca-certificates;
+    update-ca-certificates; \
-
-COPY requirements.txt /tmp/
-
-RUN set -ex; \
     \
     # python packages buildtime dependencies
     apk --no-cache add --virtual .build-deps \
@@ -60,23 +59,23 @@ RUN set -ex; \
     ; \
     apk del --purge .build-deps; \
     rm -f "/tmp/requirements.txt"; \
-    rm -rf "${HOME}/.cargo";
+    rm -rf "${HOME}/.cargo"; \
-
+    \
-# create non-root user
+    # create a non-root user
-RUN adduser -D -u 1368 duplicity;
+    adduser -D -u 1368 duplicity;
 
 USER duplicity
 
 RUN set -ex; \
+    \
+    # confirm duplicity is working
+    duplicity --version; \
     \
     mkdir -p "${HOME}/.cache/duplicity"; \
     mkdir -pm 600 "${HOME}/.gnupg";
 
 VOLUME [ "/home/duplicity/.cache/duplicity" ]
 
-# confirm duplicity is working
-RUN duplicity --version
-
 ENV \
     #################
     # BACKUP POLICY #
@@ -106,4 +105,5 @@ ENV \
     GPG_KEY_ID="" \
     GPG_PASSPHRASE=""
 
-CMD ["do-plicity"]
+COPY bin /usr/local/bin/
+COPY libexec /usr/local/libexec/

bin/kiwi-backup

@@ -0,0 +1,5 @@
+#!/bin/sh
+
+exec /usr/local/libexec/kiwi-cron/run_cron \
+  "${@}" \
+  /usr/local/libexec/kiwi-backup/scheduler

do-plicity

@@ -1,177 +0,0 @@
-#!/bin/sh
-
-#############
-# CONSTANTS #
-#############
-
-# commands
-this_exe="$(command -v "${0}")"
-ionice_exe="$(command -v ionice)"
-duplicity_exe="$(command -v duplicity)"
-
-# files
-duplicity_secrets_file='/root/duplicity_secrets'
-
-#############
-# FUNCTIONS #
-#############
-
-append_options() {
-    ao_cmdline="${1}"
-    ao_options="${2}"
-    shift 1
-
-    if [ -n "${ao_cmdline}" ] && [ -n "${ao_options}" ]; then
-        # if both are given, stitch together with a space
-        echo "${ao_cmdline} ${ao_options}"
-    elif [ -n "${ao_options}" ]; then
-        # if only options are given, output them
-        echo "${ao_options}"
-    else
-        # if at most a cmdline is given, output that
-        echo "${ao_cmdline}"
-    fi
-}
-
-print_command() {
-    pc_task="${1}"
-    shift 1
-
-    pc_cmdline="${ionice_exe} -c 3 ${duplicity_exe}"
-    pc_cmdline="$( append_options "${pc_cmdline}" "${OPTIONS_ALL}" )"
-
-    case "${pc_task}" in
-        backup)
-            pc_cmdline="$( append_options "${pc_cmdline}" "--allow-source-mismatch" )"
-            pc_cmdline="$( append_options "${pc_cmdline}" "--volsize ${BACKUP_VOLSIZE}" )"
-            pc_cmdline="$( append_options "${pc_cmdline}" "--full-if-older-than ${FULL_BACKUP_FREQUENCY}" )"
-            pc_cmdline="$( append_options "${pc_cmdline}" "${OPTIONS_BACKUP}" )"
-            pc_cmdline="$( append_options "${pc_cmdline}" "/backup/source" )"
-            ;;
-        
-        cleanup)
-            pc_cmdline="$( append_options "${pc_cmdline}" "cleanup --force" )"
-            pc_cmdline="$( append_options "${pc_cmdline}" "${OPTIONS_CLEAN}" )"
-            ;;
-        
-        rmfull)
-            pc_cmdline="$( append_options "${pc_cmdline}" "remove-older-than ${BACKUP_RETENTION_TIME} --force" )"
-            pc_cmdline="$( append_options "${pc_cmdline}" "${OPTIONS_RMFULL}" )"
-            ;;
-        
-        rmincr)
-            pc_cmdline="$( append_options "${pc_cmdline}" "remove-all-inc-of-but-n-full ${KEEP_NUM_FULL_CHAINS} --force" )"
-            pc_cmdline="$( append_options "${pc_cmdline}" "${OPTIONS_RMINCR}" )"
-            ;;
-    esac
-
-    pc_cmdline="${pc_cmdline} ${BACKUP_TARGET}"
-    echo "${pc_cmdline}"
-}
-
-print_cron_schedule() {
-    pcs_min="$(     echo "${1}" | awk '{print $1}' )"
-    pcs_hour="$(    echo "${1}" | awk '{print $2}' )"
-    pcs_day="$(     echo "${1}" | awk '{print $3}' )"
-    pcs_month="$(   echo "${1}" | awk '{print $4}' )"
-    pcs_weekday="$( echo "${1}" | awk '{print $5}' )"
-    pcs_command="${2}"
-    shift 2
-    
-    printf '%-8s%-8s%-8s%-8s%-8s%s\n' "${pcs_min}" "${pcs_hour}" "${pcs_day}" "${pcs_month}" "${pcs_weekday}" "${pcs_command}"
-}
-
-print_crontab() {
-    echo   '# crontab generated for kiwi-backup'
-    printf '# generation time: '; date
-    echo   '#'
-
-    # don't split the '#' from 'min'
-    print_cron_schedule '#_min hour day month weekday' 'command' | tr '_' ' '
-
-    print_cron_schedule "${SCHEDULE_BACKUP}"  "${this_exe} backup"
-    print_cron_schedule "${SCHEDULE_CLEANUP}" "${this_exe} cleanup"
-    print_cron_schedule "${SCHEDULE_RMFULL}"  "${this_exe} rmfull"
-    print_cron_schedule "${SCHEDULE_RMINCR}"  "${this_exe} rmincr"
-}
-
-###############
-# ENVIRONMENT #
-###############
-
-# load secrets file
-if [ -f "${duplicity_secrets_file}" ]; then
-    # shellcheck disable=SC1090
-    . "${duplicity_secrets_file}"
-fi
-
-# check if uses encryption
-if [ -n "${GPG_KEY_ID}" ]; then
-    # gpg key given
-    OPTIONS_ALL="$( append_options "${OPTIONS_ALL}" "--encrypt-key=${GPG_KEY_ID}" )"
-
-    # handle more verbose "GPG_PASSPHRASE" env_var
-    PASSPHRASE="${GPG_PASSPHRASE:-${PASSPHRASE}}"
-    export PASSPHRASE
-    unset GPG_PASSPHRASE
-else
-    # no key given
-    OPTIONS_ALL="$( append_options "${OPTIONS_ALL}" "--no-encryption" )"
-fi
-
-########
-# MAIN #
-########
-
-if [ "${#}" -gt 0 ]; then
-
-    # CLI
-    task="${1}"
-    shift 1
-
-    # run task
-    case "${task}" in
-        print-*)
-            task="${task##*-}"
-
-            case "${task}" in
-                # print out the crontab
-                crontab)
-                    print_crontab
-                    ;;
-                
-                # print out a task
-                backup|cleanup|rmfull|rmincr)
-                    print_command "${task}"
-                    ;;
-
-                # unknown task
-                *)
-                    >&2 echo "Cannot print '${task}'."
-                    >&2 echo "Choose from: crontab, backup, cleanup, rmfull, rmincr"
-                    exit 1
-                    ;;
-            esac
-            ;;
-
-        # execute single task
-        backup|cleanup|rmfull|rmincr)
-            # shellcheck disable=SC2091
-            $(print_command "${task}")
-            ;;
-
-        # unknown task
-        *)
-            >&2 echo "Unknown task '${task}'."
-            >&2 echo "Choose from: backup, cleanup, rmfull, rmincr"
-            exit 1
-            ;;
-    esac
-else
-
-    # default run: replace crontab, then start crond
-    print_crontab | crontab -
-    crond -fl 8
-fi
-
-exit 0

libexec/kiwi-backup/build_command

@@ -0,0 +1,81 @@
+#!/bin/sh
+
+#############
+# CONSTANTS #
+#############
+
+# commands
+ionice_exe="$(command -v ionice)"
+duplicity_exe="$(command -v duplicity)"
+
+# files
+duplicity_secrets_file="${HOME}/duplicity_secrets"
+
+########
+# MAIN #
+########
+
+# load secrets file
+if [ -f "${duplicity_secrets_file}" ]; then
+    # shellcheck disable=SC1090
+    . "${duplicity_secrets_file}"
+fi
+
+# check if uses encryption
+if [ -n "${GPG_KEY_ID}" ]; then
+    # gpg key given
+    options_encryption="--encrypt-key=${GPG_KEY_ID}"
+
+    # handle more verbose "GPG_PASSPHRASE" env_var
+    PASSPHRASE="${GPG_PASSPHRASE:-${PASSPHRASE}}"
+    export PASSPHRASE
+    unset GPG_PASSPHRASE
+else
+    # no key given
+    options_encryption="--no-encryption"
+fi
+
+task="${1}"
+shift 1
+
+add_space () {
+  if [ -n "${1}" ]; then
+    echo " ${1}"
+  fi
+}
+
+printf "%s -c 3 %s%s %s" \
+  "${ionice_exe}" \
+  "${duplicity_exe}" \
+  "$( add_space "${OPTIONS_ALL}" )" \
+  "${options_encryption}"
+
+case "${task}" in
+  backup)
+    printf ' --allow-source-mismatch'
+    printf ' --volsize'
+    printf ' --full-if-older-than'
+    printf '%s' "$( add_space "${OPTIONS_BACKUP}" )"
+    printf ' /backup/source'
+    ;;
+
+  cleanup)
+    printf ' cleanup'
+    printf ' --force'
+    printf '%s' "$( add_space "${OPTIONS_CLEAN}" )"
+    ;;
+
+  rmfull)
+    printf ' remove-older-than %s' "${BACKUP_RETENTION_TIME}"
+    printf ' --force'
+    printf '%s' "$( add_space "${OPTIONS_RMFULL}" )"
+    ;;
+
+  rmincr)
+    printf ' remove-all-inc-of-but-n-full %s' "${KEEP_NUM_FULL_CHAINS}"
+    printf ' --force'
+    printf '%s' "$( add_space "${OPTIONS_RMINCR}" )"
+    ;;
+esac
+
+echo " ${BACKUP_TARGET}"

libexec/kiwi-backup/scheduler

@@ -0,0 +1,9 @@
+#!/bin/sh
+
+this_script="$( readlink -f "${0}" )"
+this_dir="${this_script%/*}"
+
+echo "${SCHEDULE_BACKUP}"  "$( "${this_dir}/build_command" backup )"
+echo "${SCHEDULE_CLEANUP}" "$( "${this_dir}/build_command" cleanup )"
+echo "${SCHEDULE_RMFULL}"  "$( "${this_dir}/build_command" rmfull )"
+echo "${SCHEDULE_RMINCR}"  "$( "${this_dir}/build_command" rmincr )"